Centrifugal ore-separator.



P. F. PECK.

CENTRIFUGAL ORE SEPARATOR.

APPLICATION FILED SEPT. 17, 190B.

91 7, 121 Patented Apr. 6, 1909.

4 SHEETS-SHEET 1' lcf/zwsea P. F. PECK.

GENTRIFUGAL ORE SEPARATOR.

APPLICATION FILED SEPT. 17, 1908.

91 7,1 2 1 Patented Apr. 6, 1909. 4 SHEETS-SHEET a.

iii ll;

P. F. PEGK. GBNTRIFUGAL ORE SEPARATOR.

APPLICATION FILED SEPT. 17,1908.

Patented Apr. 6, 1909.

4 SHEETS-$HEET 4.

all whom it may concern: Beit known that'I, PHILIP *zen of the United States, residing at Chicago,

STATES PA'rEiSiT oFFicE.

PHILIP F. PECK, OF CHICAGO, ILLINOIS.

CENTRIFUGAL onn-sn'rnna'ron.

F. PECK, a citiinthe county of Cook and State of Illinois, have invented certain new and useful Iinproveinents in Centrifugal Ore-Separators,

. j. of which the following is .a specification.

' The objects of my invention are to con- I struet in improved separator employing ce'ntrifugal force and assisting agencies for separation of particles of waste and value in pulver'ized ores while mixed with liquid, of the general type illustrated and described in my applications for United States Patents, Serial l\o. 444787, filed July 22, '1908; Serial'No.

453,527, filed September 17, 1908, and Serial No. 456,060, filed October 3, 1908.

operation.

. launder in transverse central section. IS a top. plan view'of my separator.

In the acc oinpan ing drawing'Figure 1 is i a side elevation of t e rotatable portions and frame of my separator, as well as showing the Ig. 2 Fig. 3 is a transverse vertical central section of my separator, excepting the frame, which is shown in side elevation. Fig. 4- is pninci-. pally an enlarged transverse section of the eft side .of the main rotating arts, similar to that illustrated in Fig. 3, ut with the flexible portion shown partly expanded and with liquid shown present as it occurs during Fig. 5 is principally a plan of a detachedpart showing one of the cams and its drive mechanism, enlarged. Fig. 6 is an enlargedtransverse section of my separator on line 6-6 of Fig. 3, lookin in the direction of the arrows, showing a istendedstate of the flexible-portion as in Fig. 4. Fig.7 is a vertical cross section of part of the flexi- [ble covering element to the deflector ensection of Fig. 7 enlarged, on line 8-8 of larged and removed. -Fig. 8 is a transverse Fig. 7, looking in the direction of the arrows. Fig. 9 is a transverse section of Fig. '7 en- .larged, on line 9-9 of Fig. 7, looking in thedirection 'of the arrows. Fig. 10 is mainly an enlarged vertical central cross section of one sideof the deflecto member, modified.

Fig. 1] is mainly a-c1oss section of Fig. 1Q, on line 11-11, of Fig. 10, looking in thedirection of the arrows. Fig. 12 is an inside elevation of a fragmentary part of the wall of the supporting elementor deflector vessel. Fig. 13 is mostly an enlarged fragmentarcross section cf the parts for eliciting yieii able expansion, taken on line 125 .3 of

Specification of Letters Patent.

Application filed. September 17, 1908. S ei-1a 1No. 458,626.

zsel is ill the separating Patented April o, 1909.

,In making my 'unproved centrifugal separator, I provide 'a member having a separating surface, which member I have illustrated in the forni of a vessel A, with a closed bottom and substantially open top. The bottom of the vessel has a central hub B, that engages rigidly a shaft C, which is mounted in journal 7 boxes D, and D respectively to support it vertically. The journal boxes areattached to a suitable general supporting frame E of the separator, and the lower end of the shaft is stepped on an anti-friction bearing F, (Fig. 3) to carry its weight The vessel A is turned smooth and concentric to the shaft C, and on its inner wall is aseparating surface G, over which the substances to be separated pass, as hereinafterde'scribed.

The rimof the open end of the vessel is Y flanged outward as shown and indicated by 'H, which flange has an annular recess at .its' outer topfedge, into which the dependingpart of the ring I, is seated; this'depending part being. some greater inwidth than the do th of -the annular recess. in the flange I, there isleft between the ring-and the-flange, when-the two are seated together,

an annular space J The inainrpart'of thering'i's also ma'dewideenou h so it extends inward some distance tower the axis of the vessel, thereby partly closing the opening in thetop of the vessel. 1

The vessel is preferably made its walls and the se arating surface IIlCllIllIlg outward from its ttom to its top or open end, and the ring 1, extends a greater'dis tance toward the axis: than the extent of' outward slant or inclination of the-walls of -the vessel, so that the bore or opening of the ring is less in diameter than the diameter of the bottom of the vessel, enahlingwhen desired a suflieient body of the 1iquid,'su lied to the vessel, being retained therein to the separating passage and submerge the sepa-- rating surface.

The rin I is held in place on the flange of 'the vesse by the screws K, which pass anti-frlction type.

vessel by the screws WV.

merge the separating surface, as above stated.

Located inside of the vessel A, and with said vessel forming a separating passage M, I

provide a member to serve as a deflector,

which preferably embodies a substantially non-elastic su porting element or portion N that I have i ustrated in form of a vessel, although this part may-be any other suitable form of su ortistructure and I will in' I L n a most laces 1n the eclfieation refer to it as the eflector vesse This deflector vessel has a closed bottom and an open top, except that at itstop is a ring N in threaded engagement with it. smaller in diameter than the inside of the vessel A, therebyleaving the separating passage M, adjacent to the separating surface; it is also somewhat shorter than the inside of the vessel A, and has a central hub O, which securely and rigidly engages the lower portion 'of the sleeve P, that is mounted in a rotatable manner around the central shaft C.

Between the u 'per end of the hub B, and the lower end of the sleeve P, I provide a bearing Q, (Fig. 3), which is preferably of an This bearing is of sufficient thickness to hold the bottoms of the vessels A and N apart, and leave a eomparforms a feed chamber U. This ring has a central opening at its top, considerably larger than the outer diameter of the hub O, leavin an annular space around the hub through which li uid and material may be introduced into t e feed chamber U. This rin T has an outwardly extended flange at its ower edge, that fits in the recess inside of the raised boss V on the bottom of the deflector vessel, and is tightly secured to the Near the outer diameter of the feed chamber U, I provide a number of holes X, through the bottom of the deflector vessel, which serve as material and liquid passages from the feed chamber down mto the space R, whence such material and liquid actuated by centrifugal force is driven into the separating passage as hereinafter described.

The deflector member, in addition to the supporting part or element N, embodies a flexible part which I prefer to form by surrounding the circumference of the supporting art with a yieldably expansible element Y t at ma be in the nature of a suitable piece of ru ber fabric, jacket or tubing securely and appropriately fastened to the This vessel -is somewhat supporting part, bringing it into proximity to the separating surface and in part forming the separating channel. It is im ortant that the expansion of this expansi le element should be effected by means that will permit of its properly yielding .to and being com- I facilitate this end I have provided meansfor effectingthis yieldable expansion mainly by liquid pressure hereinafter more fullydescribed. I have provided the ex ansible element in this case with substantia ly nonelastic reinforcing means or strips'Z (shown best in theenlarged Figs. 6, 7 and 8,) of metal or other suitable material, to reinforce the jacket against distortion caused by its circumferential friction in the separating passage. These reinforcing means are arranged in a manner to serve the office intended, and yet permit of diametrical. expansion of the jacket element. They are illustrated as lying substantially parallel with the axis of rotation, and do not in this application extend into the zones where the fastening of the jacket to the deflector 1 means Z, are held together and to place prin-- ci ally by the rubber or equivalent substance w ich serves as binder means for them. The fastening of this expansible element to the supporting vessel or element N, is preferably effected by tightly winding several strands of wire 2 around over the desired places and twisting or otherwise suitably securing the ends of the wire together. In this way the larger part .of the circumferential area of the deflector vessel and the expansible jacket element are unattached, and form. expansion chambers 3 which are adapted to receive liquid under pressure for expanding the jacket element to enlarge the deflector and proportionately decrease the depth of the separating passage as hereinafter described. The strands of wra )ped around this expansible element esta lishes a substantially liquid tight partition or division between these expansion wire.

chambers, making them closed or practically so with respect to each other, and causes the 'expansible member to be revolved with the The num- I deflector vessel during operation. ber of theseexpansion chambers may be varied if desired, and while I prefer to have them substantially.continuous circumferentially, and have so .illustrated them, theyreceive liquid in their channels 5, while they are in a sta re of rotation. The outer circumierences oi these rings are of size to tightly fit within the inner wall of the de iiector vessel,-one of which rings is located preferably in transverse axillar alinement with each of the expansion chambers. Around through the bottoms oi these ring shaped troughs are several holes 6, extending from the channels 5 in the troughs through the wall of the deflector vessel, and communicating with their respective expansion chambers.

During operation of the separator, liquid introduced into the channels 5 is in part driven by the action of centrifugal force through the holes 6, into the, expansion chambers 3, thereby becoming expansion liquid, and by liquid pressure'distends or expands in a yieldable manner the jacket element Y, outward, enlarging the diameter of the deflector and roportionately diminishing the size or depth of the space M, which is the separating passage-rains expansion is augmented to the maximum degree at or before the commencement of the loading period of the separator. As means for introducing liquid into these channels 5, to effect expansion, there is provided a pipe 7, having" branches 8 with their delivery ends in position to fiowthe liquid into the respective channels, and in each of these branches is a valve 9, which ailords facility -l'o independently regulating the supply of liquid flowed into the difierent channels 5. 'I he degree of expansion or" the jacket or expansible element depends largely on the quantity of liquid permitted to accumulate in the channels 5, and this accumulation is governed and limited by the position of the out-er ends of the scoop conduits 10 and 10 which are of shape to bring these outer open ends to operate on and against the surface of the revolving body of liquid in the respective channels 5, thereby removing liquid and lessening the expanding pressure on the jacket element and consequently enabling enlargement of the separating assage as desired. It is advantageous that t 1e expanding pressure on this element Y be diminished graduaily as concentrates accumulate and bed in the separating passage, permitting gradual contraction of the expansible element, and proportionate gradua enlargement of the separating passage to accommodate the bed-. I, therefore, support the scoop conduits 10 and 10 respectively, that ding concentrates.

channels 5, on scpa operate in the differentwhich are suitably rate rods 11 and 11 by means of annular adapted to liquids to a mounted to be susceptible of partial rotation and have their respective u per ends 12 and 12 crooked at approximately right angles to their main body. The crooked ends respectively contact with the peripheral surfaces of different cams 13 and 13 that are mounted on rotatably journaled appropriate shafts 14 and 14, so when the cams are revolved the crooked ends of the rods are moved to conform to the surface contour of the cams, and thereby gradually rotatably move the rods 11 and 11 swinging the scooping ends of the pipes or conduits 10 and 10 out or in with respect to the axis of the separator,

' which gradually removes the liquid from the channels 5 to a greater or less distance from the axis, thus automatically and gradually regulating, varying, and limiting the expanding pressure on the expansible element, independentlyof variation of the rotating speed of the deflector member or expansible element.

The surfaces of the cams are made of suitable contour and the scoop pipes 10 and 10, and the cams are adjusted with respect to the rods 11 and 11, and the channel rings 4 in position to accomplish the removal of the quantity of liquid desired.

As means for effecting rotation of the cams, I have placedworm Wheels 15 and 15 respectively on the shafts 14 and 14, meshing" with worms 16 and 16, mounted on suitably journaled shafts 17 and 17 on which latter shafts" 1 also provide cone shaped belt pulleys 18 and 18, as illustrated. On a suitably mounted shaft 19, I have placed cone shaped pulleys 20 and 2G in proper relative belt alinement with the pulleys 18 and 18, and have provided drive belts 21 and 21, respectively connecting these two pairs of cone pulleys, by which rotation is transmitted irom the cones 20 and 20 to those 18 and 18 and to the worms and worm wheels 16 and 16 and 15 and 15 respectively, and to the came 13 and 13.

The belts 21 and 21can be moved along the cones as desired by the guides 22 and 22 to obtaingreater or less speed of rotation of the cams 13 and '13, or either of them. The shaft 19 is provided-with a pulle 23 connected by a quarter twist drive be from a pulley 25 on the u per end of the shaft C, so that the cams an their associated mechanism are revolved while the separator is in operation.

By means of the 'swiveled clamps 26 and 26 the conduits 1.0 and 10 pendently adjusted on their rods 11 and 11 to bring their scooping ends in or out into position to relatively move the expanding greater or less depthfrom the channels 5, and the delivery-ends of these conduits may terminate at any suitable place to dispose oi the removed liquid.

may be inde I have illustrated them in position to deliver into the feed chamber'U, of the separator, whence it passes through the separating passage.

5 Vvater or other liquid with material to be separated is fed to the separator from any suitable source of supply, through a conduit,

which I have shown as a Ipipe 27, with itsend entering the space ading into the feed chamber U. From the feed chamber, the liquid and material ass through the the holes X, down into t e space R, and,

actuated by centrifugal force, are driven "2'5 lows that during operation, while liquid is in the se arating passage, being actuated by centrifiigal force, and liquid is also in the expansion chambers, being actuated b centrifugal force, the expansible element is operating between two bodies of liquid under pressure and will yield in expansion or contraction as the case may be, to the body of liquid which exerts a sufiiciently greater or excess pressure to effect such result.

If it is desired to produce greater expan-. sion in one of the expansion chambers than in-another, the position of the scoop conduit which operates withrespect to that particular chamber may be adjusted on its rod independently to permit a deeper accumulation of actuating expansion liquid for that chamber, and vice versa.

During o eration of the separator the vessel or mem er carrying the separating surface is revolved at a desired rate of speed by a belt (not shown) passing around the pulley 28,'from any suitab e source of motive ower, and the deflector is revolved at asu icient 50 .speed differential to the separating surface to transmit through the instrumentalityof the liquid in, the separating passage a liquid scouring or washing friction on the separat' ing surface, or material that may be thereon to facilitate separation desired. .The liquid, which Iprefer to be water, with finely-pulverized material tobe separated, in-a state to flow freely, is introduced into'the separator through the pipes 27 hereinabove described, and is driven into the separating passage, the li uid accumulating in a sufficient body to fill the separating passage the I lighter portion ofthe material with the li uid then passes up over the separating su ace and over its top edgeinto the space J a nd to progressively following increases the differential velocity, an matically the intensity ofthe scouring force 1n the separating channel. The intensityof,

that extent the outer or scooping ends of the conduits 10 to. 10 are bein gradually moved outward by the cam mec anism gradually lessening the accumulation; of expanding liquid in the channels 5, and permitting the flexible element Y to be gradually contracted. This continues until there has been a sufficient quantit of se arated material or concentrates bed ed in t eseparatim channel to practically fill it, then the flow of water with the material for separation is stoppedby closing the valve 29, and the speedof the vessel aving the separating surface isdecreased to acomparatively' slow velocity, and clean water is introduced by means of the branch pipe 30, which connects with a suitable source of preferably clean lated by the valve 31. By this time the cams have revolved a suflicient distance to bring water supply, the volumeof which is reguthe crooked part 12 and 12of the rods 11 into position on the cam to be quickly moved and swing theouter ends of the scoops 10 and 10 inward, and again permit the maximum desired accumulation of expanding liquid in the channels 5.

The high speed of rotation of the deflector is maintained during this time, which greatly autothe securing force is automatically increased because of the movement of the scoops to a position permittin a greater accumulation of expansion liqui and also because the ex-.

panslon liquid is actuatedunder constght rotation of the deflector, while the compression or resisting force of liquid in the se arating passage is much reduced under t e de creased rotary velocity of the vessel A. The

reater friction then operating against the fledded'material, which is being held with reduced security, causes this material to uickly yield and be carried out and disc arged with the water or other liquid.

through the holes in the plugs L- Where it is caught in the launder 32, and as discharged from said launder through the opening 33, may then bediverted to any place desired.

The launder is supported by the bracket 34, e cover or top 35. After the accumulation of separated material has and has a remova been discharged, the greater speed of rotation of the vessel A is restored, the clean its diametrical walls largely cut away leaving elongated spaces 37, best shown'in detail Fig. 12. Spaced around the circumference of the supporting element 36 I have provided bars 38 extending longitudinally of the axis,- which are movably connected to the sup? porting element by means of rods 39 located at each end of and attached to the respective bars as shown. The rods 39 extend toward the axis of rotation, passingithrough ap propriate externally threaded sleeves 40, best shown in Fig 13, which sleeves are in threaded engagement with the suitably shaped and located internal flange rings 41, of the suporting element. The sleeves 40 are of Suthcient length to permit of desired adjustment in or out, by means of their screw threads, and are provided with a head or flange on their outer ends adapted to rest against the inner ends of the spiral springs 42, which are coiled around the rods or pins 39. The outer end of the springs 42 rest against the bars 38 and exert an outward pressure on the bars, forming yieldable expansion means for the expansion element 43 which surrounds the outer surface of the collective bars as hereinafter more fully explained, The.out ward or expanding pressure on the bars may be increased or diminished by screwing the sleeves 40 in or out, thereby increasing or decreasing the com ression of the springs 42. The rods 39 extend through the sleeves in a slidable manner so as to ermit the bars to move out or in while yiel ing to relative variation of the expanding and compression forces exerted on the respective sides of the expansible element, and the rods are threaded to the extent desired and engage nuts 44 adjacent to the ends of the sleeves nearest the axis of rotation, which nuts may be ad-- justed in or out to contact with the ends of the sleeves, as may be desired, to limit the movement or extent of the expansion force of the bars.

Around over the circumference of the deflector vessel or supporting element and over the collective outside area of the bars 38, l locate the expansible element 43, which serves to create a washing or liquid scouring friction in aid of separation of material during operation as has been before explained. This element 43 may be secured to the supporting element in any suitable way, as by tightly wrapping strands of Wire 45 around it. The bars being held out by the springs 42 expand the element 43 in a yieldable manner, so that by an excess pressure of the liquid in the separating channel, the springs 42 will yield and permit the element 43 to be.

compressed accordingly. The degree of expansion force and resistance to compression of the element 43 may be regulated by adjustment of the sleeves 40, out or in, thereby increasing or decreasing the pressure on the springs 41.

able expansion, liquid may also be employed inside of the expansible element as illustrated in Fig. 10, and the quantity may be regulated or limited byany suitable means, as has been explained in the main figures of the drawing.

I. desire to here explain that where in the specification and claims I have used the expression that the vessel or member having the separating surface and the member having the expansible element form the separating assage, I do not mean that they necessari y wholly form such passage, as they may only in part form it and still come within the sco e of my meaning,claims and invention. I a so desire to state that in the use of the word element. I do not mean to necessarily imply a basic or noncornposite factor.

What I regard as new and desire to secure by Letters Iatent is:

1. In a centrifugal ore separator, the combination of a rotatable member having a separating surface, a member differentially rotatable thereto in part forming with the first member a separating passage, the second member embodying an element in proximity to the separating surface which. element contains comparatively non-elastic reinforcing means and is adapted to be ex panded'during operation and to be automatically contracted by pressure of liquid in the separating passage and means adapted to supply liquid to the separating passage, substantially as described.

2. In a centrifugal ore separator, the com bination of a rotatable member having a To assist in effecting vicld- 15 separating surface, a member differentially rotatable thereto in part forming with the first member a separating passage, the second member embodying an element inproximity to the separating surface, which element contains comparatively non-elastip reinforcing means, and is adapted to. automatically yield to the relatively varying expansion and compression forces on its respective sides, efiecting substantial contraction or'enlargement of the separating passage and automatic means adapted, during operation, to var said expansion force independently of t e rotating speed of said second member, substantially as described.

3. In a centrifugal ore separator, the combination of a rotatable member having a separating surface, a member differentially rotatable thereto in part forming with the first member a separating passage the second member embodying an element in proximity to the separating surface adapted to with the treatment member a separating passage and embodying an expansible and contractibleelement, comprising com aratively non-elastic reinforcing means, an yieidable binder means,the two combined and co- 3 operating in formation of said element adapted to operate between yieldably expanding and compressing forces and to automatically yield to relatively varying pressure'of said forces, while generating a liquid wasbinfi force in the separating passage, substantia y as described.

5. In the combination of a centrifugal ore separator, having a rotatable treatment member with a separating surface, a differentially rotatable member in part forming with the treatment member a separating passage and embodying an expansible and contractible element, comprising comparativel non-elastic reinforcing means, and

'el able fibrous material,the two comined and cooperating in formation of said element adapted to operate between yieldably expandin and compressing forces and to automatical y yield to relatively varying pressure of said forces, while generating a 'quid washing force in'the separating passage, substantially as described.

6. In the combination of a centrifugal ore separator, having a rotatable treatment member with a separating surface, a differ entially rotatable member in part forming with the treatment member a separating passage and embodying an expansible and contractible element comprising com aratively non-elastic reinforcing means, eing multiple strips or bars dis osed substantiallg' iparalle to the axis 0 rotation, and iel a le fibrous material,the two comined and cooperating in formation of said element, adaptedto operate between yieldably expandin and compressing forces, and toautomatica y yield to relatively varying pressureof-said forces while generating-aliquid washing force in the separating passage, substantially as described. 7

7. In the combination of a centrifugal ore separator, having a rotatable treatment I member with a separating surface, a dril'er- Z bodies of liquid. under entially rotatable member in part forming with the treatment member, a separating passageand embodying an expansible and contractible element comprising comparatively non-elastic reinforcing means, yieldable fibrous material and elastic substance,- the three combined and cooperating in formation of said element adapted to operate between yieldably expanding and compressing forces, "and to automatically yield to the relatively varying pressure of said "forces, while generating a liquid washing force in the separating passage, substantially as described.

8. In the combination of a centrifugal ore separator, having a rotatable treatment member-with a separating surface, a differentially rotatable member in part forming with the treatment member a separating passage and embodying an expansible and contractible removable tube shaped element comprising comparatively non-elastic reinforcing means, 'ieldable fibrous material and elastic substance,the three combined and cooperating in formation of the said element, adapted to operate between yieldably expanding and compressing forces and to automatically yield to relatively varying pressure of said forces, substantially as described.

9. In a centrifugal ore separator, the combination of a rotatable member having a separating surface, a member differentially rotatable thereto in part forming with said first member a separating passage, the second member embodyingan element in proximity to the separating surface having comparatively non-elastic reinforcement means and adapted to be expanded by liquid pressure, and means adapted to supply hquid for effecting said expanding pressure, substantially as described.

10. In a centrifugal ore separator, the combination of a rotatable member forming one wall of a separating passage, a member differentially rotatable thereto in part forming the separating passage adapted to contain a body of liquid while in operation, the second member embodying an element adapted to be expanded by liquid pressure and means adapted to gradually decrease the liquid operating to effect expansion during the loading period, substantially as de; scribed. j

1 1. In centrifugal ore separator, the combination of a rotatable member having a separating surface, a differentially rotatable deflector forming with said member a separating passage, said deflector embodying a yieldable liquid actuating frictional scouring element adapted to operate between two ressure, and to be expanded or contracted bythe liquid exerting the greater pressure thereon, means for, supplying liquid on both sides of said ele'- "combination of a rotatable member having a non-expansible supporting element and an ment and means adapted to graduallyand I automatically decrease the liquid operating to effect expansion during the loading pe-" riod, substantially as described.

12. In a centrifugal ore separator, the E combination of a rotatable member having a separating surface, a member differentially l rotatable thereto, forming in part with said first member'a separating passage adapted to contain a body of liquid while in operation, the said second member embodying an exterior element having comparatively none'lastic reinforcing means and adapted to hold liquid while in operation and to be expanded and contracted by liquid pressure actuated by centrifugal force, substantially as described.

13. In a centrifugal ore separator, the combination of a rotatable member, forming one wall of a separating passage, a member differentially rotatable thereto, in part forming said separating passage adapted to contain a body of liquid while in'operation, the second member embodying a substantially expansible element adapted to hold liquid while in operation and to be )eriodieally expanded and contracted by 'quid pressure actuated by centrifugal force, means for supplying liquid for effecting said pressure and automatic means for varying the effective uantity of the last named liquid, substantially as described;

14. In a centrifugal ore separator, the

separating surface, a deflector differentially rotatable thereto,- forming with said member, a separating passage adapted to contain a body of liquid while in operation, said deflector embodying expa-nsible and contracti-- ble means-having comparatively non-elastic reinforcing elements and adapted through liquid the instrumentality of liquid pressure to be periodically expanded and contracted thereby elfecting contraction and enlargement of the separating passage, substantially as described.

15. In a centrifugal ore separator, the combination of arotatable vessel having a separating surface, a member differentially rotatable to said vessel, forming therewith a separating passage, said member embodying a'yieldable portion adjacent to the separating passage provided with substantially nonelastic reinforcing means and adapted to be subjected to liquid erssure on both of its sides while in operation, and to yield toward or from the axis of rotation forced by the liquid on its side which exerts the greater pressure thereon while generating liquid frictional force within the separating passage, and means ada ted to gradually automatically decrease tie liquid operating to effect expansion during the loading period, substa-nt1ally as described.

16. In a centrifugal ore separator, the combination of a rotatable member having a separating surface, a member, differentially rotatable thereto forming with said first member a separating passage, the second member embodying y1eldab1e elements forming areas adapted to be expanded by pressure, having substantially nonelastic reinforcing elements, and means whereby liquid expansible pressure may be gradually and automatically varied on parts of said elements to a greater degree than on other parts thereof, substantially as described.

PHILIP F. PECK.

Witnesses M. PncK, W. H. PEoK. 

